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Bioanalysis Using Dried Blood Spots: The Biggest Advancement in Bioanalysis Since LC–MS-MS?A discussion on the analytical challenges that both liquid chromatography and mass spectrometry face as well as some potential solutions to these issues.
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Advances in TOF-MS-Based Screening for Food Safety Residue Analysis with a Positive ApproachMass spectrometry plays an increasingly significant role in the analysis of residues and contaminants in food. Here we will illustrate how the combination of ultrahigh-pressure liquid chromatography (UHPLC) and high-resolution time-of-flight-mass spectrometry (TOF-MS) is used to generate a screen of veterinary drug residues in products of animal origin. The use of UHPLC–TOF-MS and dedicated, workflow directed software allows rapid screening for large numbers of residues and automated quantification of positive samples. In addition, we illustrate how the data generated using MSE acquisition mode enable critical structural information to be collected, which offers additional selectivity and confirmatory data for compound identification and facilitates elucidation of the structure of newly discovered compounds.
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Simultaneous Determination of Formononentin, Biochanin A, Daidzen and Genistein in Trifolium pratense (Red Clover) by HPLCA simple and rapid HPLC method was established to simultaneously determine the active ingredients of red clover.
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UHPLC Coupled with Fourier Transform Orbitrap for Residue AnalysisThe trend in residue analysis has changed from target-oriented procedures towards accurate mass full-scan MS techniques. This article describes these developments and addresses the implications of 2002/657/EC.
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Comprehensive Characterization of Monoclonal Antibodies Using a Microfluidic Chip-Q-TOF PlatformAccurate, sensitive, and comprehensive characterization of monoclonal antibodies is an absolute necessity to the pharmaceutical and diagnostic industries to meet regulatory requirements and ensure the efficacy and safety of the final product. Microfluidic chip-based high performance liquid chromatography technology interfaced with the mass accuracy of quadrupole time-of-flight mass spectrometry provides the ability to rapidly and efficiently assess the quality of intact monoclonal antibodies, confirm their amino acid sequence, and determine their glycosylation state, while consuming very small amounts of these precious products.
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Mastering Pressure Management in GPC/SEC SystemsThis installment of Tips & Tricks deals with pressure monitoring for GPC/SEC systems and gives hints for efficient troubleshooting to solve issues that are identified in the laboratory.
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Using Two-dimensional Liquid Chromatography to Separate Complex Mixtures of PeptidesTwo-dimensional liquid chromatography (2D-LC) allows analysts to deal with complex samples that either cannot be adequately separated by one-dimensional liquid chromatography (1D-LC) or require excessively long analysis times. Peptide mixtures, whose characterization is relevant in many areas (e.g., proteomics, food analysis, pharmaceutical, life sciences), are a clear example of such complexity. An overview of the most used 2D-LC modes of operation is presented and several examples of their use for the separation of peptide mixtures are described.
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Toward a Universal Detector for Small Molecule Applications: Direct-EI in LC–MSThis article describes the operating principles of the direct-electron ionization (EI) interface, which is becoming more popular in many LC–MS applications. Matrix effects and the role of direct-EI as a universal detector for small molecule analysis are also discussed in detail. The advantages and drawbacks of this approach are described and a comparison with atmospheric pressure ionization (API) interfaces is made. The potential of direct-EI is illustrated with a selection of practical applications.
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Are You Sure You Understand USP <621>?In this column, we look at the current version and the update of USP <621> on high-performance liquid chromatography (HPLC) that becomes effective 1st May 2025.
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Rapid LC Determination of UV Filters in Cosmetics using Ethanol as the Mobile PhaseA rapid and environmentally friendly LC method for the simultaneous determination of 12 UV filters in cosmetic samples using ethanol as the mobile phase.
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Quantitative Proteomic Workflow for Discovery of Early Rejection Kidney Transplant Peptide Biomarkers and Subsequent Development of SRM Assays in UrineThe accurate diagnosis of renal allograft rejection currently depends upon a biopsy. Transplant medicine would benefit greatly from the availability of noninvasive tests for early detection of rejection and immunosuppressive drug therapeutic monitoring. Only a limited number of studies have been published to date on specific proteins associated with allograft rejection. Typically, renal dysfunction due to humoral transplant rejection or other pathologies results in the increase of protein excreted in urine (1–5). In blood, endogenous peptides (not generated by trypsin digestion ex vivo) are likely candidate biomarkers for many diseases and pathologies as they are secreted from tissues and enter the bloodstream (6,7). The analysis of endogenous protein and peptide fragments in urine can provide a noninvasive, early indication of kidney transplant rejection or disease.
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Real-Time Profiling of Volatile Malt Aldehydes Using Selected Ion Flow Tube Mass SpectrometryThe authors use headspace SIFT-MS to target and identify volatiles in various malt aldehydes. The specificity and speed are compared to current methodology.
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Analysis of Polymers and Protein Nanoparticles using Asymmetrical Flow Field-Flow Fractionation (AF4)This article describes some of the latest developments for the analysis of polymers and nanoparticles.
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GCxGC-FID for Qualitative and Quantitative Analysis of PerfumesExploring the use of GCxGC-FID as a technique for qualitative and quantitative analysis of perfumes
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Monitoring Emissions From Respiratory Medical Devices in Accordance With ISO 18562-3This study describes the monitoring of potentially harmful volatile organic compounds (VOCs) emitted from respiratory medical devices, by pumped sampling and thermal desorption–gas chromatography–mass spectrometry (TD–GC–MS) analysis in accordance with ISO 18562 part 3. Emissions from two sets of face-mask supply tubing and three nasal cannulas were compared, and all were found to emit VOCs at levels that may give cause for concern.
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Harnessing the Benefits of HPLC with Fluorescence Detection for the Analysis of Aflatoxins in Raw MilkThis article highlights the analytical advantages of analyzing raw milk for aflatoxins, focusing on M1, using high performance liquid chromatography (HPLC) with fluorescence detection - without derivatization. Leveraging M1’s native fluorescence, this is particularly welcome since this approach affords the requisite analytical sensitivity with minimal method complexity.
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Rapid Screening of Pesticides Using U-HPLC/MSThe screening of pesticides, mycotoxins, and veterinary drugs is of great importance in regulated environments such as food or feed analysis. Due to some of the limitations of traditional triple quadrupole approaches (for example, targeted analyte detection, limited number of compounds, and unidentified unknown compounds), there is currently a trend towards use of full-scan MS data for the analysis of residue samples. Current screening approaches mainly rely on the use of ToF instruments coupled to U-HPLC delivering mass accuracy (~5 ppm) at a maximum resolution of <15,000. This can produce inaccurate mass measurements due the presence of unresolved background matrix interferences. In this work we show a full-scan MS screening approach with the Thermo Scientific Exactive mass spectrometer, a novel single-stage Orbitrapâ„¢ MS capable of providing precise mass accuracies at resolutions of up to 100,000 without the need for internal mass calibration.
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Automated Solid Phase Extraction for Efficient Extraction of Fluoroquinolone Antibiotics from FishThe global demand for fish as a natural source of fresh animal protein, essential fats, minerals, and vitamins continues to rise with the human population.
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Simultaneous Determination of Formononentin, Biochanin A, Daidzen and Genistein in Trifolium pratense (Red Clover) by HPLCA simple and rapid HPLC method was established to simultaneously determine the active ingredients of red clover.
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Evaluation of Extraction Methods and Bias Correction by EPA Method 6800 Protocol for Mercury Species in Tuna Fish Tissue Using an Ion Chromatograph Coupled to an ICP–MSMercury pollution mainly originates from industrial activities such as chlorine production, garbage incineration and above all coal-fueled power generation. The US Environmental Protection Agency (US EPA) considers mercury as highly toxic with a pronounced accumulative and persistent character.
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Method Selection for Trace Analysis of Genotoxic Impurities in PharmaceuticalsThis article describes methods to quantitatively analyse genotoxic and potentially genotoxic impurities in pharmaceutical ingredients
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Simultaneous Headspace-GC–FID Analysis for Methanol and Ethanol in Blood, Saliva and Urine: Validation of Method and Comparison of SpecimensA simultaneous headspace-GC–FID method was validated to establish methanol and ethanol assessment in blood, urine and saliva.
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High Resolution UHPLC Analysis of Naringin in Grapefruit JuiceGrapefruit juice was analysed by gradient UHPLC for naringin - a major flavanoid in grapefruit juice that gives it its bitter taste. A ZORBAX Rapid resolution HD (RRHD) StableBond-C18 2.1 ? 150 mm, 1.8 ?m column was able to resolve over 60 peaks, including naringin in 7 minutes, and was re-equilibrated in just three minutes by operating at a high flow rate (0.8 mL/min). The high pressure generated (965 bar) is well within the 1200 bar operating range of the RRHD column and 1290 Infinity LC.
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Screening by LC–MS-MS and Fast Chromatography: An Alternative Approach to Traditional Immunoassays?A new technique was developed based on liquid chromatography coupled with tandem mass spectrometry to analyze drugs that are not part of current immunoassay screening, specifically zolpidem, zopiclone, and zaleplone, or "z-drugs."
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Method Development for Drug Impurity Profiling (Part 2)A systematic approach to developing drug impurity profiling methods.
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Method Development for Drug Impurity Profiling (Part 2)A systematic approach to developing drug impurity profiling methods.
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UHPLC Coupled with Fourier Transform Orbitrap for Residue AnalysisThe trend in residue analysis has changed from target-oriented procedures towards accurate mass full-scan MS techniques. This article describes these developments and addresses the implications of 2002/657/EC.
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Dual Flow ChromatographyDual flow chromatography (DFC) separations are performed with back and forth flow for rapid method development, design of experiments (DOE), quality-by-design (QbD), or high-throughput chromatographic purification. Although different than conventional unidirectional flow through chromatography, chromatographic principles still control the separations. Selectivity coefficients and Langmuir adsorption isotherms control the separation chemistry properties of the column and dictate the mobile phase conditions needed to achieve separation. However, the kinetic rates of diffusion and interaction of mobile phase molecules with the stationary phase, column channeling, and other column properties are not germane to the practice of DFC. Chromatographic conditions developed with DFC can be scaled to any size, including laboratory and industrial preparative columns.
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Innovations and Strategies of Sample Preparation Techniques to Reduce Matrix Effects During LC–MS/MS BioanalysisReducing matrix effects during LC–MS/MS bioanalysis is paramount. Improving sample preparation techniques is the best way to combat this issue.
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Diamonds are a Chromatographer's Best Friend?Pavel Nesterenko from ACROSS about his work on the potential of diamond-related substances as stationary phases
